Subtract 28/40 from 42/80
42/80 - 28/40 is -7/40.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 40 is 80
Next, find the equivalent fraction of both fractional numbers with denominator 80 - For the 1st fraction, since 80 × 1 = 80,
42/80 = 42 × 1/80 × 1 = 42/80 - Likewise, for the 2nd fraction, since 40 × 2 = 80,
28/40 = 28 × 2/40 × 2 = 56/80 - Subtract the two like fractions:
42/80 - 56/80 = 42 - 56/80 = -14/80 - After reducing the fraction, the answer is -7/40
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